Enlighten can provide indirect lighting for Directional Light, Spot Light and Point Light actors.

Set the light actor's Mobility to Movable to make it use dynamic lighting and shadows. You can then move the light and change the color in game. Enlighten provides the indirect lighting.

To control a light's effect on Enlighten indirect lighting, select the actor and edit the properties in the Details panel.

Enlighten saturation

Set the radiosity color saturation. 0 is completely desaturated.

Enlighten only

Generate radiosity without direct lighting. If enabled, the light isn't seen by Lightmass.

Use dynamic Enlighten shadows

By default, the light from a Spot Light actor may leak through walls, even when Cast Dynamic Shadows is enabled. This occurs when the cone of the Spot Light actor intersects surfaces in the shadow of the wall.

To prevent this, you can enable Cast Dynamic Enlighten Shadows. This tells Enlighten to use the dynamic shadow information to limit the effect of the direct light. This option only affects Spot Light actors with Mobility set to Movable, and Cast Dynamic Shadows enabled.

To see the effect of the direct light, select the Spot Light actor and in the Show menu, enable Enlighten > Sampled Direct Lighting.

Disable dynamic Enlighten shadows

If you don't need this feature in a particular level, you can save memory by disabling it for that level. To do this:

1. Select the EnlightenSystemContainer within the level.
   

2. In the Details pane, under Enlighten Settings, disable Allow Gpu Input Shadowing.
   

   After you uncheck Allow Gpu Input Shadowing for a given level, Cast Dynamic Enlighten Shadows has no effect for lights that illuminate that level.

Use static shadows

To eliminate the cost of UE4 dynamic shadows for a Movable light, you can set the mobility of the light to Stationary. Enlighten provides the indirect lighting, and the shadows are baked using Lightmass when you build lighting for the level.